Have you been doing the main quest, "All that goes bump"?
Around 28% completion you should've had a prompt to find a way into the night shop where you meet Sam. Visit the shop at night and it will ask for a password. You find out that nobody knows the password from the dinner time rumors. Then when you visit the lake shop again you can threaten to kick down the door and she will let you in.
Viewing post in Camp Mourning Wood - Katey comments
Oh good point. So if you're playing the demo from Itch.io you won't have access to all of the gloryhole scenes. The full version of the game has nearly all the girls that can visit the gloryhole. You can check out my Patreon here =)
https://www.patreon.com/cw/exiscoming